---What are you busy with ?--- We are carrying out a research _______ the causes of cancer.
Her husband had ___ a large business during his lifetime.
I’ll ___ the matter as soon as possible.Just have a little patience.
I don't know this part of the countryside well, so we’d better ___ the path.
The news soon ___ its way throughout the country.
Now even the middle school students go abroad for study ___.