Scientists are trying their best to_______ ways to treat the terrible disease caused by Ebola(埃博拉).
---What do you _____the transportation in our city? --- Great!
---What's thirty and fifteen? --- It’s _______.
Don't me, I can look after well.
---What about _________ hiking this week? __ Great. I’d like _________ with you.
—___________________—He is going fishing.