Scientists are convinced ________the positive effect of laughter________ physical and mental health.
Trains are all kinds of goods to Lhasa through the Qinghai-Tibet Railway day and night.
Paris has some great museums ______ visitors can see fine works ofimpressionist painters.
I’ve made several travel plans for our vacation, but I’ll leave it to you ______ one.
Based on a true story, the film shows a hero racing ______ time to get back the stolen papers.
The landlady prefers to have women in the apartment rather than men. She thinks women take ______ care of things!