Usage note
自从表示从某个时间点开始一直到现在。
Zìcóng biǎoshì cóng mǒu gè shíjiān diǎn kāishǐ yīzhí dào xiànzài.
Since indicates starting from a certain point in time up to now.
Context note
自从我学会骑自行车，我每天都骑车上学。
Zìcóng wǒ xuéhuì qí zìxíngchē, wǒ měitiān dōu qíchē shàngxué.
Since I learned to ride a bike, I ride to school every day.
5 examples
自从开学，我认识了很多新朋友。
zì cóng kāi xué， wǒ rèn shi le hěn duō xīn péng yǒu。
Since school started, I have met many new friends.
自从下雨，天气变凉了。
zì cóng xià yǔ， tiān qì biàn liáng le。
Since it rained, the weather has become cooler.
自从他来了，教室更热闹了。
zì cóng tā lái le， jiào shì gèng rè nào le。
Since he came, the classroom has become livelier.
自从我养了小狗，我每天都很开心。
zì cóng wǒ yǎng le xiǎo gǒu， wǒ měi tiān dōu hěn kāi xīn。
Since I got a puppy, I am happy every day.
自从学了中文，我能看懂很多故事。
zì cóng xué le zhōng wén， wǒ néng kàn dǒng hěn duō gù shì。
Since I learned Chinese, I can understand many stories.
5 mini stories
自从春天来了，花儿都开了。小鸟也回来了。
zì cóng chūn tiān lái le， huā ér dōu kāi le。 xiǎo niǎo yě huí lái le。
Since spring came, the flowers have all bloomed. The birds have also returned.
自从我学会游泳，我经常去游泳池。游泳很有趣。
zì cóng wǒ xué huì yóu yǒng， wǒ jīng cháng qù yóu yǒng chí。 yóu yǒng hěn yǒu qù。
Since I learned to swim, I often go to the pool. Swimming is very fun.
自从妈妈做了蛋糕，我一直想吃。蛋糕很甜。
zì cóng mā ma zuò le dàn gāo， wǒ yì zhí xiǎng chī。 dàn gāo hěn tián。
Since Mom made a cake, I have been wanting to eat it. The cake is very sweet.
自从我有了新书，我每天读一页。书很好看。
zì cóng wǒ yǒu le xīn shū， wǒ měi tiān dú yí yè。 shū hěn hǎo kàn。
Since I got a new book, I read one page every day. The book is very good.
自从我们种了花，花园变漂亮了。我们每天浇水。
zì cóng wǒ men zhǒng le huā， huā yuán biàn piào liang le。 wǒ men měi tiān jiāo shuǐ。
Since we planted flowers, the garden has become beautiful. We water them every day.
Mini dialogue
自从开始学中文
A
自从开始学中文，我每天都练习写字。
Zìcóng kāishǐ xué Zhōngwén, wǒ měitiān dōu liànxí xiězì.
Since I started learning Chinese, I practice writing characters every day.
B
我也是，自从上了中文课，我觉得进步很快。
Wǒ yě shì, zìcóng shàngle Zhōngwén kè, wǒ juéde jìnbù hěn kuài.
Me too, since I took Chinese classes, I feel I'm improving quickly.
自从下雨后
A
自从昨天下雨，天气变冷了。
Zìcóng zuótiān xià yǔ, tiānqì biàn lěng le.
Since it rained yesterday, the weather has become cold.
B
对，自从下雨后，我穿上了外套。
Duì, zìcóng xià yǔ hòu, wǒ chuān shàngle wàitào.
Yes, since it rained, I put on a jacket.
Related words and contrasts
related
从
cóng
from
自 and 从 both mean 'from', combined as 自从.
related
以后
yǐhòu
after; later
Often used with 自从: 自从...以后 (since...).
contrast
因为
yīnwèi
because
自从 indicates time, 因为 indicates reason.