“A跟B一样/相同” means A and B are the same after comparison. The structure “A跟B一样” can take an adjective to indicate the aspect being compared. “跟, 和’’ are interchangeable in this structure.
这件衣服跟那件(衣服)一样/相同。(Zhè jiàn yīfu gēn nà jiàn (yīfu) yīyàng / xiāngtóng.) This dress is the same as that one.
你的年纪跟他一样大。(Nǐ de niánjì gēn tā yīyàng dà.) You are as old as him.
我跟你一样，都喜欢做饭。(Wǒ gēn nǐ yīyàng, dōu xǐhuān zuò fàn.) Same as you, I also like cooking.
我的爱好跟你一样。(Wǒ de àihào gēn nǐ yīyàng.) I have the same hobby as you.
The negative form:
A跟B + 不一样 / 不(相)同
A跟B + 不一样（+ Adjective）
这件衣服跟那件(衣服)不一样/不(相)同。(Zhè jiàn yīfú gēn nà jiàn (yīfú) bù yīyàng.) This dress is different from that one.
我的想法跟你不同。(Wǒ de xiǎngfǎ gēn nǐ bù tóng.) My ideas are different from yours.
你的年纪跟他不一样大。(Nǐ de niánjì gēn tā bù yīyàng dà.) You are not the same age as him.
A 不如 B (+ Adjective)
This structure indicates that A is not as well as B in a certain aspect.
喝茶不如喝咖啡。(Hē chá bùrú hē kāfēi.) It’s better to drink coffee than tea.
你不如你妈妈漂亮。(Nǐ bùrú nǐ māma piàoliang.) You are not as pretty as your mother.
“A有B + Adjective” means A is as “Adjective” as B. This comparison is generally only used in questions, but statements. B is usually preferred by the speaker. “这么” or “那么” means as much, so much. In this case, B is already very good in this aspect of “adjective”.
茶有咖啡好喝吗？(Chá yǒu kāfēi hǎo hē ma?) Is tea as tasty as coffee?
>> The premise is that coffee is tasty in the mind of the speaker.
姚明有大卫那么高吗？(Yáomíng yǒu Dàwèi nàme gāo ma？) Is Yao Ming as tall as David?
>> The premise is that David is already very tall.
The negative form：
A没有B（+ 这么/那么）+ Adjective
茶没有咖啡（这么/那么）好喝。(Chá méiyǒu kāfēi (zhème/nàme) hǎo hē.) Tea is not as good as coffee.
姚明没有大卫（这么/那么）高。(Yáomíng méiyǒu Dàwèi (zhème/nàme) gāo.) Yao Ming is not as tall as David.
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