be boastful

基本解释

The wisest way is not to be boastful .
最聪明的办法是别去瞎说。
translation-dictionary.net
And you're right, the Americans should not be boastful in this regard.
你说得对，美国不该在这方面自吹自擂。
The trick is starting the discussion of a subject without appearing to be boastful moralizing or unnatural.
这其中的诀窍是：展开的话题不致使人感到不自然，或显得自夸，以及有道德化倾向。
blog.sina.com.cn

There's some hubris in this kind of talk--but Ghosn is entitled to be boastful.
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Hooker is proud of his accomplishment but has a good reason not to be too boastful.
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