Relative clauses complete the sentences with who for people and that for things. 2. i can't find the key opens this door. 3. it was a math was difficult to win. 4. a waiter is someone serves people in a restaurant. 5. there's a shop in our road is open all time. 6. i met the girl won the competition. 7. these are the letters arrived this morning. 8. which neighbour do you mean? the one works in the bank?

I can't find the key that opens this door.
It was Math that was difficult to win.
A waiter is someone who serves people in a restaurant.
There's a shop in our rood that is open all the time.
I met the girl who won the competition.
These are the letters that arrived this morning.
Which neighbour do you mean? The one who works in the back?