I haven’t eaten this kind of food before.

=> This is (a)  

They will catch all the prisoners again by tonight.

=> All the prisoners (a)  

The last time I went to Ho Chi Minh City was ten years ago.

=> It (a)  

No, please don’t tell him.

=> It'd rather (a)  

Although he was very tired, he tried to help me with my homework.

=> Tired as (a)  

The child will die if nobody sends for a doctor.

=> Unless (a)  

I’m sorry that I didn’t finish my homework last night.

=> I wished (a)  

We spent 5 hours getting to London.

=> It took (a)  

The children couldn’t go swimming because the sea was rough.

=> The sea was too (a)