understanding可数吗

understanding是不可数名词，表示“了解;理解; 领会”，但是如果前面有修饰词修饰时则可以跟不定冠词，have a better understanding of ...表示“充分理解……”。课本句子中understanding前有better修饰，所以前面加了不定冠词a。

exercise的用法

英文单词：exercise

翻译中文意思|用法|音标|

exercise: [ 'eksəsaiz ]

n. 练习,作业,运动

v. 练习,运动,运用

词形变化:

形容词:exercisable 动词过去式:exercised 过去分词:exercised 现在分词:exercising 第三人称单数:exercises

例句与用法:

1. What others think exercises a great influence on most of us.

别人怎样想对我们多半会产生很大影响。

2. If you don't get more exercise, you'll get fat.

如果你不多作运动，就会发胖。

3. The doctor advised him to take more exercise.

医生建议他多运动.

4. Doing crosswords gives the mind some exercise.

做纵横字谜游戏能锻炼脑筋.

5. Jogging is a healthy form of exercise.

慢跑是有益健康的锻炼方式.

6. Horses get fat and lazy if they are not exercised.

马不训练就会增膘、 变懒.

7. This problem is exercising our minds very much at the moment.

这一问题此刻使我们很伤脑筋.

8. I am very much exercised about the education of my son.

我对儿子的教育十分操心.

英英解释:

名词exercise:

1. the activity of exerting your muscles in various ways to keep fit

同义词：exercising, physical exercise, physical exertion, workout

2. the act of using

同义词：use, usage, utilization, utilisation, employment

3. systematic training by multiple repetitions

同义词：practice, drill, practice session, recitation

4. a task performed or problem solved in order to develop skill or understanding

同义词：example

5. (usually plural) a ceremony that involves processions and speeches

动词exercise:

1. put to use

同义词：exert

2. carry out or practice; as of jobs and professions

同义词：practice, practise, do

3. give a workout to

同义词：work, work out

4. do physical exercise

同义词：work out

5. learn by repetition

同义词：drill, practice, practise

competition是可数名词吗

competition 英[ˌkɒmpəˈtɪʃn]

美[ˌkɑ:mpəˈtɪʃn]

n. 竞争; 比赛; 竞争者; [生] 生存竞争;

[例句]It took hot competition from abroad, however, to show us just how good Scottish cashmere really is.

然而，我们是通过来自国外的激烈竞争才认识到了苏格兰羊绒的优良品质。

[其他] 复数：competitions 形近词： repetition appetition compe*****y

repetition有复数的吗

repetition

[英][ˌrepəˈtɪʃn][美][ˌrɛpɪˈtɪʃən]

n.

重复，反复; 背诵; **品，副本; [乐]复唱，复奏，重奏;

复数：repetitions

repetitions

[英][repɪ'tɪʃnz][美][repɪ'tɪʃnz]

n.

反复; 重复( repetition的名词复数 ); **品; 副本;