这是我爸爸。
This is my father.

Explain:
这 this
是 am/is/are
我 I
爸爸 father
Notes:
“这是我爸爸。” means “This is my father.” This phrase is a common expression when introducing one's father to another person. Here “爸爸(father) ” can be replaced by any person. And “我(I) ” is a shortened form of “我的(my)”. This is quite common in oral Chinese.

他做什么工作？
What’s his job? / What does he do?
Explain:
他 he
做 do
什么 what
工作 job
Notes:
“他做什么工作？” means “What’s his job? / What does he do?” Such a sentence is used to ask someone’s profession or career, this is a common topic when people are talking about somebody.

我妈妈是老师。
My mother is a teacher.
Explain:
我 I
妈妈 mother
是 am/is
老师 teacher
Notes:
“我妈妈是老师。” means “My mother is a teacher” This sentence is used to describe someone's profession or career. Please take notice of the words “老师” which may substitute for any professions.

我们家有四个人。
There are four people in my family.
Explain:
我们家 our family
有 there be
四个人 four people
Notes:
“我们家有四个人。” means “There are four people in my family.” “有” is a typical character which means “there is/are…” or somebody has something. “个” is a frequently used measure word.

孩子多大了
How old are your children?
Explain:
孩子 children
多大 how old
了 (past tense marker)
Notes:
“孩子多大了？” means “How old are your children? ” This question is especially for asking about the age of children. In contrast with the westerners, generally Chinese people don't mind talking about the age, and have a habit of inquiring about the age of children to show friendship. When you ask about the age of an old person, you need add “年纪(age)” after “多大”.

儿子八岁，女儿六岁。
My son is eight and my daughter is six.
Explain:
儿子 son
女儿 daughter
八 eight
岁 years old
六 six
Notes:
“儿子八岁，女儿六岁。” means “My son is eight and my daughter is six.” This sentence is often used as one of the common answer to the preceding question “孩子多大了？”

我属马。
I was born in the year of Horse.
Explain:
我 I
属 Chinese sign
马 horse
Notes:
“我属马。” Means “I was born in the year of Horse.” This sentence refers to Chinese Zodiac, which is the rat, the ox, the tiger, the rabbit, the dragon, the snake, the horse, the sheep, the monkey, the rooster, the dog and the pig respectively. According to an old legends Buddha (the ultimate Emperor for the whole universe in Chinese legend) gave each animal a year in the cycle and declared that anyone born in that year would resemble the animal in some way. If you're familiar with Chinese astrology, you may know what animal marks the year you were born in according to the calendar.

家人都好吗？
How is your family?
Explain:
家人 family
都 all
好 good/ well
吗 (a particle used at the end of questions)
Notes:
“家人都好吗？” means “How is your family?” This is a conventional greeting, and is used when you meet your acquaintances and give your regards to their family.

你老家是哪里？
Where is your hometown?
Explain:
你 you
老家 hometown
是 am/ is/ are
哪里 where
Notes:
“你老家是哪里？” means "Where is your hometown?" In China, this is a very useful expression of starting a conversation when you want to make friends with someone. And if you come from the same place, your relationship becomes close quickly.

北京/福建。
Beijing. / Fujian.
Explain:
北京 Beijing
福建 Fujian
Notes:
“福建。” means “Beijing. / Fujian.” This phrase is usually used as an example of replying to the preceding question, “你老家是哪里？” Here “北京/福建。” can be replaced by any places.