Differences between 楽しがちに、楽し気味に、楽しげに、楽しっぽく

Question

Which one of the words above is most suitable in the following sentence and why?

近所の子供たちが校庭で________遊んでいる。

Thanks!

Answer 1

The correct answer is 楽しげに. This げ roughly means "-looking", and it attaches mainly to a relatively small set of adjectives that describe emotion. 楽しげ is listed as a standalone na-adjective in jisho.org. Similar words include 悲しげ, 眠たげ, 嬉しげ and さびしげ. See also: What is the usage of 〜げ and how does it differ from 〜そう or 〜っぽい? and Difference between 〜げ　and 〜そう

がち and 気味 are wrong because they only attach to a noun or the masu-stem of a verb.

• 病気がち, 遠慮がち, 曇りがち.
• 風邪気味, 遅れ気味, 押し気味.

-っぽい can attach to many words including i-adjectives:

• with i-adjectives: 青っぽい "blueish", 安っぽい "cheap-looking"
• with nouns: 色っぽい, 理屈っぽい, 子供っぽい
• with verbs: 忘れっぽい, 飽きっぽい

When it attaches to the stem of an i-adjective, it forms another i-adjective with an added nuance of "-ish" or "-looking". It's not used with adjectives of emotion. っぽい used like this is not a productive suffix, and you cannot combine an arbitrary i-adjective with っぽい. We can say 安っぽい and 荒っぽい, but not 高っぽい nor 優しっぽい.

(As an exception, you can use っぽい after the dictionary-form of arbitrary adjectives and verbs, although this sounds fairly colloquial: 合ってるっぽい "looks correct", 高いっぽい "looks expensive", 泣いてるっぽい "seems to be weeping". See: 安いらしい, 安いそうだ, and 高っぽい are incorrect?)