To solve the traffic problem, more and more bridges ____________ across the river every year.

The students are cleaning their classroom. _____ are cleaning the windows. _____ are cleaning the chairs.

Lucy had few close friends. So she didn’t know ________ about the trouble.

Do you know why he left so early ?–__________ for the English test, I guess..

There’s milk in the fridge. Let’s go to buy some .