まだお話中です。

まだお話中です。

The line is still busy.

まだお話中(はなしちゅう)です。

Mada ohanashichū desu.

未だ (まだ、いまだ)

as yet; hitherto; only; still; not yet (with negative verb); more; besides; unfinished; incomplete; not yet finished with

お話し中 (おはなしちゅう)

busy (phone)

です (です)

be; is

Readings: ワ、はな.す、はなし

Meanings: tale, talk

Readings: チュウ、なか、うち、あた.る

Meanings: in, inside, middle, mean, center