【题目】I have to ________ for the speech contest next week, so I can't go out with you for a picnic.

【题目】If you want to make a difference to the world, you have to ________ yourself first.

【题目】Traveling around big cities by taxi can________ a lot of money, but it's usually convenient to take the underground.

【题目】After discussing two hours, we ________ to solve this problem in another way.

【题目】I'm sorry that I can't drive you to the airport. I ________ my car to my friend just now.

【题目】I sent an email to Mr. Wang last weekend. But he didn't ________ to me.

【题目】Where did you ________ the schoolbag? It looks beautiful.

【题目】Nick ________ the football players so well that their skills improved a lot.

【题目】It's best not to run away from our problems. We should always try to ________ them.