Question 13: Tomatoes__________ before they are completely ripe. A. should be picking B. can be picked C. can pick D. needn't pick Question 14: "Giao Thua" is the most sacred time of the year,__________ the first houseguest to offer the first greeting is very important. A. otherwise B. however C. so D. because Question 15: There__________ available in his area of specialization. A. is a lot of job B. are lots of job C. are a lot of jobs D. is a lot of jobs Question 16: After I copied all the information I needed from the hard drive, I__________ the computer and left. A. turned on B. switched on C. looked for D. turned off Question 17: Mal used to go to school on foot, __________? A. didn't Mai B. didn't she C. did Mai D. did she