无法识别字符串MA60

老师麻烦帮忙看下这个止损策略，出现无法识别的字符串MA60，改怎样修改呢？Params Numeric MA60Period(60); // MA60均线周期Vars Series MA60(0); // MA60均线Events OnBar(ArrayRef<Integer> indexs) Begin // 计算MA60均线 MA60 = Average(Close, MA60Period); // 如果持有多头仓位且价格触碰到MA60均线，执行平多仓操作 If MarketPosition == 1 AND (High >= MA60 OR Low <= MA60) Begin Sell(\"Long Stop at MA60\", 1, Close); End; // 如果持有空头仓位且价格触碰到MA60均线，执行平空仓操作 If MarketPosition == -1 AND (High >= MA60 OR Low <= MA60) Begin BuyToCover(\"Short Stop at MA60\", 1, Close); End; End