Clean

`->` Thì hiện tại đơn: every day

Đáp án: must buy it

`->` Vì dưa hấu rất ngon nên chúng tôi phải mua nó

Đáp án:$1$

`->` Vì 100×1 vẫn =100

I am good, thank you.

`->` S + be +adj/adv

`19-9=10`

Suy ra` 10 <9`

Chị xem câu của em có đúng không ạ. Mong chị tick cho em:((

  trung bình cộng từ 1 đến 9 là: `(1 + 2 + 3 + 4 + 5 + 6 + 7 + 8 + 9) : 9 = 5  `

Đáp số: `5`

${\left(a^2+b^2+2\right)}^2-{\left(2ab-2\right)}^2$

$=\left(a^2+b^2+2-2ab+2\right)\left(a^2+b^2+2+2ab-2\right)$

$=\left(a^2+b^2-2ab+4\right){\left(a+b\right)}^2$

Phân tích đa thức sau thành nhân tử: `2x^2 + 2y^2 - 4x - 18`

Câu 51: She’s always worried about the _________________ of her family. A. safe B. safety C. safely D. safeguard Câu 52: Don’t leave the light on. It wastes _________________. A. electric B. electrician C. electricity D. electrify Câu 53: This river is very _________________ for swimmers. A. dangerous B. danger C. endanger D. endangered Câu 54: Studying _________________ helps you to become a good cook. A. cook B. cooker C. cooking D. cookery Câu 55: Our life is much better with the help of modern _________________. A. equip B. equipment C. equipped D. well-equipped Câu 56: A fairy _________________ changed Little Pea’s rags into beautiful clothes. A. magic B. magical C. magically D. magician Câu 57: Her father soon died of a _________________ heart. A. break B. breaking C. broke D. broken Câu 58: My mother told me a very _________________ story yesterday. A. interesting B. interested C. interestingly D . interestedly Câu 59: Xuan Lam is much _________________ in history. A. interesting B. interested C. interestingly D. interestedly Câu 60: _________________, I lost my keys on the way home. A. Fortunate B. Unfortunate C. Fortunately D. Unfortunately