They were best friends and spent a lot of time together.

Meaning: The old woman and her cat were very close and enjoyed each other's company.

Choice of Words: Best friends are people who are very close and like to spend time together. Spent means used or passed (time). Time is the period during which something happens.

Alternative Expressions

They were inseparable and enjoyed each other's company immensely.

Meaning: This sentence describes two people who were always together and loved being in each other's company.

Choice of Words: They refers to the two people who were close. Were indicates that this was a past event. Inseparable means they were always together. Enjoyed indicates that they had positive feelings towards each other's presence. Each other's means they both felt this way. Company refers to being together. Immensely means a great amount.

They were thick as thieves and had a blast hanging out.

Meaning: This sentence describes two people who were very close and had a lot of fun spending time together.

Choice of Words: They refers to the two people who were close. Were indicates that this was a past event. Thick as thieves is an idiom meaning they were very close. Had indicates possession. A blast means a great time. Hanging out means spending time together casually.

Related Expressions