20 + 1 = 21 nha . Mik chúc bn học tốt
63 + 27 - 27
= 63 + ( 27 - 27 )
= 63 + 0
= 63
Viết lại câu sử dugnj từ gợi ý:
1.Already/Teddy/meet/Tet/.
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2..Yet/Penny/not buy/a present for Judy.
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3.You/call/him/yet/?/
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4.I/not see/my friends/for a long time.
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5.You/live/in your house/since last year?
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