看图

prefix:前面加
suffix：后面加

       <el-form-item label="车辆载重" :label-width="formLabelWidth">
            <el-input
              v-model="form.name"
              placeholder="请输入"
              autocomplete="off"
            >
              <i slot="suffix" style="font-style: normal; margin-right: 10px"
                >吨</i
              >
            </el-input>
          </el-form-item>