Emma: I want to make a chocolate cake, but the chef hasn't put any nice recipes on my favourite cooking blog. Gran: There's a good chocolate cake recipe in my cookbook. But, oh dear. Harry any chocolate! Emma: Hmm. I at your cookbook. Is there a lemon cake recipe in it? Gran: Let's look. Yes, there's a recipe on page 12. We it yet, but it looks nice. Let's try it. Emma: OK. We need two lemons, three eggs, some flour, butter and sugar. Ten minutes later ... Emma: OK. The cake is in the oven. Gran: Oh dear! We the lemon juice! Emma: Don't worry! Let's put some jam on the cake.