【题目】She studies ________ to make great progress.

【题目】Look! The sign over there warns us ________ in the river.

【题目】They always have a partythe third Friday in November.

【题目】Mary often helps wash the d after dinner.

【题目】We can protect our country by ________ the air, the water and the land.

【题目】Books of Mark Twain always make people _________.

【题目】Benny is only seven, he doesn’t even know ________ electricity is.

【题目】— ____is it from your home to your school?

【题目】When the bus stopped, some people ________ and some others ________.

【题目】Look at these beautiful flowers. Who gthem here? Your grandfather?