A manned mission (a) to Mars would allow a more (b) in depth study of the Red Planet , and many have argued that construction (c) a permanent base on Mars is much more (d) practical than build one on the Moon (d) Here, which two underlined sections need to be changed to correct the sentence?
আপনি আমাকে যেকোনো প্রশ্ন করতে পারেন, যেমনঃ
Are you sure to start over?