As an onomatopoeia:

"吧" can be used to imitate the sound of something breaking or snapping, such as the sound of a pencil lead breaking or a gun firing. For example, "吧的一声，笔尖断了" (Bā de yī shēng, bǐjiān duàn le) means "With a snap, the pencil lead broke." 

As a verb:

In some regional dialects, "吧" can mean to draw on or smoke a pipe. For instance, "他吧了一口烟" (Tā bā le yī kǒu yān) means "He took a puff of his cigarette." 

As a noun:

"吧" is also the Chinese translation of the English word "bar", referring to a small drinking establishment or a counter where drinks are served. For example, "酒吧" (jiǔ bā) means "bar" or "pub". 

As an interjection:

"好吧" (Hǎo ba) means "OK" or "all right", expressing agreement.

"走吧" (Zǒu ba) means "Let's go", expressing a suggestion or command.

"他明天大概不会来了吧" (Tā míngtiān dàgài bù huì lái le ba) means "He probably won't come tomorrow", expressing uncertainty.

"说吧,不好;不说吧,也不好" (Shuō ba, bù hǎo; bù shuō ba, yě bù hǎo) means "If you say it, it's not good; if you don't say it, it's also not good", indicating a dilemma or hesitation. 

"吧" can be used at the end of a sentence to express various tones, including agreement, suggestion, command, or uncertainty. It can also be used in the middle of a sentence to indicate a pause or hesitation. For example:

        As a question particle:

"吧" can be used at the end of a question to make it sound more tentative or to seek confirmation from the listener. For example, "您就是王老师吧?" (Nín jiùshì Wáng lǎoshī ba?) means "Are you Teacher Wang?" with a tone of polite inquiry.