sentences

[contiluo]

Please check the following sentences out. Which is preferable?

1. On that day, I forgot to take my watch with me to the party,
so I couldn't tell my mom what time she should pick me up.

2. On that day, when I went to the party, I forgot to take my watch
with me, so that I couldn't tell my mom what time she should pick
me up.

[emsr2d2]

Please check the following sentences out. Which is preferable?

1. On that day, I forgot to take my watch with me to the party,
so I couldn't tell my mom what time she should pick me up.

This suggests that you forgot your watch and, as a result, you couldn't tell your mum what time to pick you up - it was an accident.

2. On that day, when I went to the party, I forgot to take my watch
with me, so that I couldn't tell my mom what time she should pick
me up.

The use of "so that" suggests that you didn't accidentally forget to bring your watch, that you actually did it on purpose specifically in order to make sure that you couldn't tell your mum what time to pick you up. The word "forgot" almost sounds sarcastic.

See above. As you can see, there is a difference depending on whether you use "so" (as a result) or "so that" (in order to ensure that).