尽, 净, 一齐, 一同: nothing but, all together
【六07】副词 / adverbs (范围)
Tone colorsā tone 1á tone 2ǎ tone 3à tone 4a neutral
尽 (jìn) / 净 + 是 + noun means "nothing but, only": 这个箱子里净是旧书. Before a verb, 净 + V means "do nothing but": 他净说好听的. The tone is often one of reproach or complaint. 净 is the more spoken of the two; 尽是 is also found in writing.
一齐 says that several people act at the same moment: 大家一齐动手, 学生们一齐站了起来. It takes no companion and is never used with a single agent.
一同 means "together, along with" and accepts a companion (与他一同出发, 我和朋友一同去); it is more formal than 一起, which covers both cases with no nuance. With no companion named, 一同 needs a plural subject: 我们一同努力.
Do not confuse this 尽 (jìn, "nothing but") with the 尽 (jǐn) of 尽量 ("as much as possible").
Examples
这个箱子里净是旧书。
Zhège xiāngzi li jìng shì jiù shū.This box is full of nothing but old books.
老师一说下课，学生们一齐站了起来。
Lǎoshī yì shuō xiàkè, xuéshengmen yìqí zhàn le qǐlái.The moment the teacher said class was over, all the students stood up at once.
周末我和几个朋友一同去爬山。
Zhōumò wǒ hé jǐ ge péngyou yìtóng qù pá shān.This weekend I'm going hiking together with a few friends.
楼道里尽是自行车和旧纸箱，根本走不过去。
Lóudào li jìn shì zìxíngchē hé jiù zhǐxiāng, gēnběn zǒu bu guòqù.The stairwell is full of bikes and old cardboard boxes, there is no way through.
他净说好听的，一件事也没做成。
Tā jìng shuō hǎotīng de, yí jiàn shì yě méi zuò chéng.He does nothing but say pleasant things and has never got anything done.
我们愿意与贵公司一同努力，把这个项目做好。
Wǒmen yuànyì yǔ guì gōngsī yìtóng nǔlì, bǎ zhège xiàngmù zuò hǎo.We are willing to work together with your company to make this project a success.
Common mistakes
✗ 他一齐我去 → ✓ 他和我一同去 (一齐 takes no companion; 一同 does).
✗ 他一齐把作业做完了 → ✓ 他一口气把作业做完了 (一齐 needs several people acting at the same moment).
✗ 他净是说好听的 → ✓ 他净说好听的 (净是 goes with a noun; before a verb, 净 does without 是).