已知 2x=3y=10, 那么 12xy=?

将一批树苗种在应该正方形花园边上，四角都种，如果每隔 3 米种一棵，那么剩下10课树苗 ,如果每隔 2 米种一棵那么种满正方形的 3 条边 ,则这批树苗有 ( ) 棵

The little girl is ignorant _____ the basic rules of English grammar。

In most countries, the metric system has been _____ for all measurement.

Edison tested more than one thousand materials to see if they could _____ electric ; current and glow.

How can you _____ and watch the country go to ruin?

To begin some activity is to _____ doing it.

You've only got a slight cold. You'll _____ it in a day or two.

He read the story _____ - for everybody present to hear.

He is very _____ and well-qualified, so he should reach the top of this profession.