单选题Economics, several courses of which I have taken thus far,（）to be difficult but useful for almost all students。A proveB havebeenprovedC provesD areproved

50 We are thus led to distinguish, within the broad educational process which we have been so far considering, a more formal kind of education -- that of direct tuition or schooling. In undeveloped social groups, we find very little formal teaching and training. These groups mainly rely for instilling needed dispositions into the young upon the same sort of association which keeps the adults loyal to their group.

I think I must have ______ my purse at home.

A. forgotten

B. missed

C. left

D. taken

A、moreover

B、however

C、therefore

D、thus

This is _____ the most difficult job I have ever tackled.

A:by rights

B:by itself

C:by oneself

D:by far

Furthermore, humans have the ability to modify the environment in which they live, thus subjecting all other life forms to their own peculiar ideas and fancies.

Metaphor is used in ________.

A、To be allowed, no, invited, into the private lives of strangers, and to share their joys and fears, was a chance to exchange the Southern bitter wormwood for a cup of mead with

B、eowulf or a hot cup of tea and milk with Oliver Twist.

B、“It is a far, far better thing that I do, than I have ever done …”

C、Part of the problem is that women in America are much more brainwashed and content with their roles as second-class citizens than blacks ever were.

D、I have done the work -- … while man reaped the rewards, which is almost invariably the lot of women in politics.

A、It was shown late until midnight

B、It was starred by a few famous people

C、Far from. I should have stayed home watching TV

D、I was seated far away in the corner

I have()some courses and software to my Smartphone, and I find they are interesting and easy to use.

A. uploaded

B. downloaded

C. copied