Be assertive and spell out exactly how you feel.

自信点，把你的真实感受详细说出来。

《柯林斯英汉双解大词典》

You have to be assertive and cordial.

你必须要非常自信、很热忱。

youdao

You need to be assertive and claim control of your time.

你需要坚定的控制你的时间。

youdao

You might have to be assertive to get the service folks to do the job.

WSJ: Why Do Coupes Cost More Than Sedans?

The U.S needs to be assertive also with other countries in Latin America that maintain relations with Iran.

CENTERFORSECURITYPOLICY: Center For Security Policy

If you do want to have a conversation, Purcell says, be assertive but not aggressive in your approach.

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