Please choose the correct ending to complete the given sentence: Youth: [header] How to know if you're too old for something [title] Know your limits. [step] What you can and can't do will change with time and age. Perhaps what you could do at age 6 you can't do at age 16.

Ending1: If you know you are not in the right physical or mental condition to do something, you probably shouldn't do it. You should also avoid doing anything that gets unsafe with a certain size or weight. Ending2: Maybe think about things you'd rather try before age 16. [title] Consider doing activities that make you happy. Ending3: But it's important to know your limits so you can decide how you can decrease them. [substeps] Take an adult for a blood test (systolic blood tests) every six months. Ending4: Whatever it is that you do now that you are older, take a second to identify your limits. The more you know, the more likely you are to be able to change what you might do by age 7.

Answer format: ending1/ending2/ending3/ending4