In Quick Succession

It was all very short notice. First Arrow #1 came back from finishing his second year studies. Then he received an offer to complete his studies in the UK. Next thing you knew, he was at the airport and off!
Then Arrow #2 came back from being posted in Switzerland for his internship. He was home for 2 weeks. A good time indeed.
But the time flew by quick and he was off back to Singapore!
And now we are back to just one Arrow at home....