Open the brackets and write the correct form of the verbs. 1. This work (to do) very carefully by the investigators.

2. Yesterday he (to tell) to prepare a speech.

3. The famous scientists

(to introduce) to our students a couple of hours ago?

4. The article (not to publish) last week, if I am not mistaken.

5. Classical and modern methods of chemical analysis (to use) in the examination of drugs.

6. These pharmacists ( not to train) at Britain colleges.