rxjs/Rx没有导出成员forkjoin

我正在尝试使用ForkJoin…它在node\u modules/rxjs/Rx中找不到ForkJoin,并抛出错误ForkJoin不是rxjs/Rx的成员。

import { forkJoin } from 'rxjs';
ngOnInit() {
      forkJoin([
      this.vehicleService.getMakes(),
      this.vehicleService.getFeatures(),
      this.vehicleService.getVehicle(this.vehicle.id)]).subscribe(data => {
      this.makes = data[0];
      this.features = data[1];
      this.vehicle = data[2];
      }, err => {
        if (err.status == 404)
          this.router.navigate(['/home']);
      });