Do u know what is bond and what is equity?

China buys bonds, the only expectation is to collect bond's interest, why China or other bond investors care about if it is a blackhole or not? bond investors only care about if bond seller bankrupt or not. When u buy a CD from a bank, do u care if the bank is a black hole? u only care if the bank will belly up or not, right? You are confusing bond investment and equity investment.

you said "so many government intervention in this year?"?, can u list interventions? I can only list one which is to rescue BSC. Other government action are normal government functions, like changing interest rate, lending money to banks or investment firms. Otherwise why do we need a government? A big job of federal reserve is to stabilize the market, that is how FED were born and why we need them.

Do more reading and give more facts before u claim anything.