I was reading a grammar and saw this.

Achievement verbs describe actions that occur instantaeously.

• He solved the problem.
• He spotted the airplane.

These verbs fall into two classes - one is 'punctual', and the other 'change of state'

(..cut..)

• Change of state - find a solution, cross the finish line - This involves a preliminary activity that culminates in the act denoted by the verb. Thus, a person searches before finding the solution, and runs toward the finish line before crossing it.

(..cut..)

With change of state verbs, progressive aspect may or may not be possible, depending on whether the activity leading up to the achievement is treated as being the same activity

For example,

• 'His train is arriving at noon.' is acceptable
• '* She is recognizing the thief.' is not acceptable.

I feel that 'She is recognizing the thief.' is strange, but as I don't understand the bolded part, I can't get the reason. Would you help me with this?

I was reading a grammar and saw this.

Achievement verbs describe actions that occur instantaeously.

• He solved the problem.
• He spotted the airplane.

These verbs fall into two classes - one is 'punctual', and the other 'change of state'

(..cut..)

• Change of state - find a solution, cross the finish line - This involves a preliminary activity that culminates in the act denoted by the verb. Thus, a person searches before finding the solution, and runs toward the finish line before crossing it.

(..cut..)

With change of state verbs, progressive aspect may or may not be possible, depending on whether the activity leading up to the achievement is treated as being the same activity

For example,

• 'His train is arriving at noon.' is acceptable
• '* She is recognizing the thief.' is not acceptable.

I feel that 'She is recognizing the thief.' is strange, but as I don't understand the bolded part, I can't get the reason. Would you help me with this?