The students are ___ young people between the ages at between the age of sixteen and twenty.

He had __________ little education that he couldn’t teach __________ little children.

The waiting lists for a bed in a public elderly care home in Beijing have grown ________ long that some are saying it could take 100 years to get a position.

One should remain ______ and think of ways to escape when facing danger.

When you drive home, you can’t be＿＿＿＿＿＿＿careful.