以下是一些具有激勵性的英文美句：
1. "Success is not final, failure is not fatal: It is the courage to continue that counts." - Winston Churchill
2. "Do what you can, with what you have, where you are." - Theodore Roosevelt
3. "Life is 10% what happens to you and 90% how you react to it." - Charles Swindoll
4. "Believe you can and you're halfway there." - Theodore Roosevelt
5. "Success is not the destination, but the journey." - Zig Ziglar
6. "You miss 100% of the shots you don't take." - Wayne Gretzky
7. "The best way to predict the future is to create it." - Abraham Lincoln
8. "Life is like a box of chocolates, you never know what you're gonna get." - Colonel Sanders (although this is more of a joke, it does have a positive message of unexpected surprises in life)
9. "Opportunities are like rabbits; they come when you're not looking and then they're gone." - English Proverb
希望這些句子能夠給你帶來一些激勵和正能量！