This is a great question! Your grammar is perfect! I would just point out that single-digit numbers are spelled out in a sentence in American English unless there are also numbers greater than nine, in which case all numbers are represented with numerals (until you get to seven-digit numbers, then the rules change). Here are some examples: I have three cats, but I really want five. I have 3 cats, but I really want 10. I have 10 cats!