Without friendship, one won’t be happy _____ he is very rich.

---Good to see you again. It’s almost three years _______ we met last time.---Yes, how time flies.

---__________was your vacation? ---Very good. 

—May I go swimming this afternoon? — I'm afraid not _______ you have finished your homework.

The book was written in _________ easy English _________ even primary school students could understand it.