语法填空（共10小题，每小题1.5分，满分15分）
If you walked past the supermarket, you would find many foods that have been treated 小题1: (kill) any harmful germs that might have been in them. Milk is a good example. Raw milk --- that is, milk just as it comes from the cow --- may be 小题2: (safe) to drink. But 小题3: the milk is heated and then cooled, the harmful germs are killed. The man 小题4: discovered this way of treating milk was a Frenchman by the name of Louis Pasteur.
In the supermarket you would also find many frozen foods --- frozen fruits, vegetables, meat and fish. As techniques for 小题5: (freeze) food are being improved, more frozen foods are appearing on the market, and more people are buying them. Fruits and vegetable to be sold in the supermarket are often frozen the moment 小题6: are picked. The 小题7: fruits and vegetable are frozen, the better. 小题8: machines are often taken into the fields where 小题9: food grows, so that little time is lost 小题10: picking and freezing.