----under a microscope ,a sresh snowflake has a delicate six

非谓语
12、the microscope is rather difficult______.
A to repair B to be repaired C repairing D being repaired
为什么
13、don’t leave your feet____.Have yourself well.
A exposing; covering B exposing; covered C exposed; covering D exposed; covered
为什么
14、George set out _________himself in English.
A improve B to improve C improving D improved
为什么
15、it’s no good _____problems with a man like him.
A to discuss N discussed C discussing D to be discussed
为什么

一道英语单选
When our university laboratory bought this microscope,we were given a year's_____
A.reservation.B,security C.proof,D.guarantee
但是这句话该怎么理解?为什么选D?...

英语翻译
The microscope and telescope,with their capacity to enlarge,isolate and prode,demonstrate how details can be magnified and seperated fron the whole.
One of the attractive features of the course was the way thepractical work had been integrated withi the theretical aspects of the subject.

since i couldn't see anything through the microscope,____my careful adjustment,i gave up
since i couldn't see anything through the microscope,____my careful adjustment,i gave up.
A.for all B.after all
意思是尽管.尽管后面应该接一个句子吧,但是这里是一个名词短语.
我选B,不用毕竟的意思,字面上是在什么之后的意思,all修饰my adjustmen.

24.This is the microscope ______ which we have had so much trouble.
A) at
B) from
C) of
D) with
为什么是D呢,of不行吗

选择正确答案 through microscopes people can see objects that ___ to the naked eye.
选择正确答案
Through microscopes people can see objects that ___ to the naked eye.
(a)invisible (b)the invisible (c)are invisible (d)are the invisible
[请解释为何要选那个答案]

英语翻译
2.9.Scanning electron microscope (SEM)
The C.albicans KCTC7122 was resuspended in PBS,to a final concentration
of 108 cells/ml.200 ll aliquots of C.albicans suspension
were incubated with 22 ll of 250 lg/ml di-K19Hc.For a control,the
same amount of C.albicans suspension was mixed with 22 ll of
0.01% acetic acid and incubated for 5 min at 30 2C.The di-K19Hctreated
or untreated C.albicans samples were then fixed in 0.05 M sodium
cacodylate buffer (2% glutaraldehyde,2% paraformaldehyde,pH
7.2) for 4 h.After fixation,the samples were centrifuged at 2000 rpm
and rinsed three times for 20 min each with sodium cacodylate buffer.
The samples were then dehydrated through a graded ethanol series
(50%,70%,90%,95%,100% ·2),for 30 in each.The samples were
freeze-dried for 8 h,and coated with a light coat of gold palladium.
The specimens were then viewed with an S-2400 scanning electron
microscope (Hitachi,Japan).
3.Results
3.1.Peptides
The primary amino acid sequences of the synthetic halocidin
congeners used in this study,di-K19Hc and K19Hc,are shown
in Table 1.Table 1 also provides the sequences of P18 and
buforin II,used as the standard peptides in this study.

The microscope is rather difficult___.
A.to repair
B.to be repaired
C.repairing
D.being repaired

英语翻译：when you look through the microscope .you see what you may have looked like a long time ago ,at least in part