1. If you open up any medicine cupboard in the world, there is a high probability that you will find aspirin and penicillin. 1) that you will find aspirin and penicillin. 同位语从句，对probability的内容加以说明。 There is little probability that he will succeed. 2）open up 打开，打[展]开; 开办[设]; 开发[辟]; 揭开; 开口(说话), 透露; 开火 Open up. let me go in. They decided to open up a business in the town. A machine gun opened up.