Terraform Import aws resources

Hey, We previously imported ec2 instance under terraform management and now we want to bring ec2 root volume under terraform management as well.
On my testing I was able to import ec2 instance and ebs volume using the following commands

terraform import aws_ebs_volume.id vol-01234
terraform import aws_instance.myec2 i-12345678

Please help me how I can import aws_instance.root_block_device ?