丸い; 円い

まるい

round, circular

i-adjective

Conjugation Table

Present

丸い

Negative

丸くない

Past

丸かった

Past Negative

丸くなかった

Te Form

丸くて

Adverbial

丸く

Conditional

丸ければ

Presumptive

丸いでしょう

Example Sentences

そのボールは丸いです。

That ball is round.

Sono bōru wa marui desu.

昨日、丸いケーキを食べました。

Yesterday, I ate a round cake.

Kinō, marui kēki o tabemashita.

この帽子は丸くないです。

This hat is not round.

Kono bōshi wa marukunai desu.

Grammar Notes & Usage Tips

•Conjugation Basics**: As an i-adjective, 丸い (まるい) follows standard i-adjective rules: for example, "not round" is 丸くない (まるくない), and "was round" is 丸かった (まるかった).

•Particle Pairing**: When describing something as round, use 丸い with the particle が or は, such as ボールは丸い (ボールはまるい) meaning "The ball is round."

•Nuance in Kanji**: Both 丸い and 円い mean "round," but 丸い is often used for three-dimensional objects like balls, while 円い is more about flat, circular shapes like coins.

•Common Mistake**: Don't confuse 丸い with 丸くする (まるくする), which means "to make something round"; remember that 丸い simply describes the shape, while 丸くする indicates an action.

•い-adjective: Conjugates by changing the い ending