I know you can't learn a language in three weeks, but let's see how I fail.
How much can I learn before my granny from Ethiopia visits?
I'm unemployed so I have time to study and I'm pretty motivated. You can often get from 0 to A1 level in a language within 100 hours of study.
I should be able to learn the writing system (it's a hard one), more than 100 words, and some amount of grammar.
First half-day: I've got the eight pronouns solidly memorised, and about 20% of the written characters. At this pace I'll get to about 300 words, simple sentences, and will be able to read slowly, sounding things out.