6. Underline the correct or most likely answers. 1. I`m waiting /I`ve been waiting here for ages.
2. I`ll join you in the restaurant. I`m waiting /I`ve been waiting for my colleagues.
3. The markets have/had a sharp fall last week.
4. The markets have/had a sharp fall this week.
5. If you need the instruction manual, I`ve left/I left it on your desk.
6. I`ve left/I left the instruction manual on your desk.
7. A: How long are you working/have you been working here?
B: About 2 years. I joined the company when they opened this branch.
8. A: How long are you working/have you been working here?
B: About 2 weeks. Then It`s on Chicago. Head Office send me all over the world.
9. We can`t supply the goods because they haven`t paid/didn`t pay the deposit.
10. We couldn`t supply the goods because they haven`t paid/didn`t pay the deposit.
11. I`m waiting for Sue. When have you last seen/did you last see her?
12. I`m waiting for Sue. Have you seen/Did you see her?

7. Complete the sentences with the time expressions in the list. Several answers may be possible but one solution uses each expression in the most appropriate way: yet, for, since, often, ever, never, already, so far, just, always.
1. I`ve lived in my city-center flat 2009. I love it there.
2. Thanks for the present! I`ve wanted a gold Rolex!
3. We`ve interviewed for candidates this morning, and none of them is really suitable for the job.
4. Have you worked abroad?
5. I`ve heard that we`ve won the contract! Congratulations everybody!
6. Hurry up! Haven`t you finished ?
7. Nina has worked in this company over five years now.
8. I`ve been to a karaoke bar before. It`s certainly an interesting experience.
9. I`ve passed this building, but this is the first time I`ve been inside.
10. We`ve been very busy on the stand this morning. we`ve given away over 200 brochures.

8. Underline the correct or most likely answers.
1. Wait for me. I`ll be/I`ve been ready in a moment.
2. We need to move forward – we can`t just wait until the economy recovers/will recover.
3. That looks very heavy. Will I/ Shall I help you?
4. Notice. This elevator is going to be/ will be out of service until further notice.
5. Look out! It`s going to fall/ It`ll fall!
6. A: Do you want me to call them?
B: No, it`s all right, I`ll do/I`m doing it.
7. Please don`t leave until I come back/will come back.
8. Julie won`t be here next week. She`ll work/ She’ll be working at our other office.
9. The flight attendant is calling us. I think we will/we`re going to board the plane.
10. They`ll probably/ They probably will cut back the training budget next year.

Sure, let's go through the questions one by one.

Question 6:

1. I`m waiting / I`ve been waiting here for ages.
- The correct answer is "I've been waiting here for ages". We use the present perfect continuous tense to express an action that started in the past and is still happening at the present moment.

2. I`ll join you in the restaurant. I`m waiting / I`ve been waiting for my colleagues.
- The correct answer is "I'm waiting for my colleagues". In this case, we use the present continuous tense to talk about an action happening at the present moment.

3. The markets have / had a sharp fall last week.
- The correct answer is "had a sharp fall last week". We use the past simple tense to talk about a completed action in the past.

4. The markets have / had a sharp fall this week.
- The correct answer is "have a sharp fall this week". We use the present simple tense to talk about something happening repeatedly or regularly.

5. If you need the instruction manual, I`ve left / I left it on your desk.
- The correct answer is "I've left it on your desk". We use the present perfect tense to talk about a past action with a present result or connection.

6. I`ve left / I left the instruction manual on your desk.
- Both answers can be correct here, depending on the context. If you are talking about a recent action, then "I've left" would be more suitable. If you are talking about a completed action in the past, then "I left" would be the correct answer.

7. A: How long are you working / have you been working here?
- The correct answer is "have you been working here?" We use the present perfect continuous tense to talk about an action that started in the past and is still happening at the present moment.

8. A: How long are you working / have you been working here?
- The correct answer is "have you been working here?" Again, we use the present perfect continuous tense to talk about an ongoing action.

9. We can`t supply the goods because they haven`t paid / didn't pay the deposit.
- The correct answer is "haven't paid the deposit". We use the present perfect tense to talk about past actions with a present result or connection.

10. We couldn't supply the goods because they haven't paid / didn't pay the deposit.
- The correct answer is "didn't pay the deposit". We use the past simple tense to talk about completed actions in the past.

11. I`m waiting for Sue. When have you last seen / did you last see her?
- The correct answer is "did you last see her?" We use the past simple tense to talk about past actions that are not connected to the present.

12. I`m waiting for Sue. Have you seen / Did you see her?
- The correct answer is "Have you seen her?" We use the present perfect tense to talk about actions that happened at an unspecified time before the present moment.

Question 7:

1. I`ve lived in my city-center flat since 2009. I love it there.
- The correct answer is "since". We use "since" to talk about an action or event that started at a specific time in the past and is still happening.

2. Thanks for the present! I`ve wanted a gold Rolex!
- The correct answer is "I've always wanted a gold Rolex". We use "always" to talk about an action or state that has been true or happening for a long time in the past and continues to the present.

3. We`ve interviewed for candidates this morning, and none of them is really suitable for the job.
- The correct answer is "several times". We use "several times" to talk about an action that has been repeated more than once.

4. Have you worked abroad?
- The correct answer is "ever". We use "ever" to ask if a person has had the experience of doing something in their life.

5. I`ve heard that we`ve won the contract! Congratulations everybody!
- The correct answer is "already". We use "already" to talk about an action that has happened before the present time.

6. Hurry up! Haven`t you finished yet?
- The correct answer is "yet". We use "yet" to talk about something that is expected to happen or is necessary, but it has not happened or been done at the time of speaking.

7. Nina has worked in this company for over five years now.
- The correct answer is "for". We use "for" to talk about the duration of an action or state.

8. I`ve been to a karaoke bar before. It`s certainly an interesting experience.
- The correct answer is "I've never been to a karaoke bar before". We use "never" to talk about an action or state that has not happened at any time in the past.

9. I`ve passed this building, but this is the first time I`ve been inside.
- The correct answer is "so far". We use "so far" to talk about the actions or events that have happened up until now.

10. We`ve been very busy on the stand this morning. We`ve given away over 200 brochures.
- The correct answer is "often". We use "often" to talk about actions or events that happen many times.

Question 8:

1. Wait for me. I`ll be ready in a moment.
- The correct answer is "I'll be ready in a moment". We use the future simple tense to talk about actions that will happen in the future.

2. We need to move forward – we can`t just wait until the economy will recover.
- The correct answer is "recovers". We use the present simple tense to talk about general truths or facts.

3. That looks very heavy. Shall I help you?
- The correct answer is "Shall I help you?" We use "shall" to offer assistance or make suggestions.

4. Notice. This elevator is going to be out of service until further notice.
- The correct answer is "is going to be". We use the future continuous tense to talk about actions that will be happening in the future.

5. Look out! It's going to fall!
- The correct answer is "It's going to fall!" We use the present continuous tense to talk about future actions that have already been planned or arranged.

6. A: Do you want me to call them?
- B: No, it's all right, I'll do it.
- The correct answer is "I'll do it". We use the future simple tense to talk about actions that will happen in the future.

7. Please don't leave until I come back.
- The correct answer is "come back". We use the present simple tense to talk about scheduled or planned actions in the future.

8. Julie won't be here next week. She'll be working at our other office.
- The correct answer is "She'll be working". We use the future continuous tense to talk about actions that will be happening in the future.

9. The flight attendant is calling us. I think we're going to board the plane.
- The correct answer is "we're going to board". We use "going to" to talk about future intentions or plans.

10. They'll probably cut back the training budget next year.
- The correct answer is "They'll probably cut back". We use the future simple tense and "probably" to express a high possibility or likelihood in the future.