Example sentences
tā他de的qī妻zǐ子shì是lǎo老shī师。
His wife is a teacher.
wǒ我qī妻zǐ子hěn很xǐ喜huan欢chàng唱gē歌。
My wife likes singing.
About this word
妻 is "wife" and 子 is the neutral-tone noun suffix, the same one in 孩子 and 桌子, so 妻子 is not "wife and child". In classical Chinese the word did mean "wife and children", and the modern sense is the narrower one that survived. 妻子 itself is neutral and slightly formal. 太太 is polite, 老婆 is what you call her at home, and 夫人 is for someone else's wife, usually in a formal setting. 我妻子 works anywhere.
The story behind the character
妻
妻 is a hand seizing a woman by the hair. In the bronze and oracle bone forms you can see it: a hand on top, a woman below, her long hair pulled. The old reading is marriage by capture, and the character keeps the moment of it. Xu Shen had a kinder take: 妻，婦與夫齊者也, a wife stands level with her husband.
子
子 is a newborn drawn from life. Big head, arms stretched out, legs swaddled together. The oldest forms are exactly that, and Xu Shen simply marked it 象形, a picture. It is also the first of the twelve earthly branches, the one paired with the rat, which is why the character shows up on old calendars and in the zodiac.