1. four

2. 4

1. probability

2. odds (Tw)

1. anxious

2. worried

3. apprehensive

1. frequency

1. rule (e.g. of science)

2. law of behavior

3. regular pattern

4. rhythm

5. discipline

1. to worry

2. anxiety (about)

1. ratio

2. rate

3. proportion

1. birthrate

1. Chinese set expression, typically of 4 characters, often alluding to a story or historical quotation

2. idiom

3. proverb

4. saying

5. adage

6. CL:條|条[tiáo],本[běn],句[jù]