diff --git a/pyinfinitensor/src/pyinfinitensor/onnx.py b/pyinfinitensor/src/pyinfinitensor/onnx.py
index 03b6866f..a429368f 100644
--- a/pyinfinitensor/src/pyinfinitensor/onnx.py
+++ b/pyinfinitensor/src/pyinfinitensor/onnx.py
@@ -63,7 +63,7 @@ def from_onnx(model: onnx.ModelProto):
             (alpha, beta, transA, transB) = (
                 attributes[name] for name in ["alpha", "beta", "transA", "transB"]
             )
-            # TODO 不支持这些参数
+            # FIXME 不支持 `alpha` `beta`
             assert alpha == 1.0
             assert beta == 1.0
             tensors[node.output[0]] = handler.matmul(
@@ -226,7 +226,7 @@ def from_onnx(model: onnx.ModelProto):
                 tensors.get(node.output[0]),
             )
         elif node.op_type == "Flatten":
-            # TODO 后端算子不支持沿任意轴展开
+            # FIXME 后端算子不支持沿任意轴展开
             axis = next(
                 (attr.i for attr in node.attribute if attr.name == "axis"), None
             )
diff --git a/src/ffi/ffi_infinitensor.cc b/src/ffi/ffi_infinitensor.cc
index 9300cdb8..37b7d5da 100644
--- a/src/ffi/ffi_infinitensor.cc
+++ b/src/ffi/ffi_infinitensor.cc
@@ -30,7 +30,7 @@ void init_graph_builder(py::module &m) {
         m, "CpuRuntimeObj");
     py::class_<TensorObj, std::shared_ptr<TensorObj>>(m, "TensorObj");
     py::enum_<ActType>(m, "ActType")
-        .value("Linear", ActType::None) // None 是 Python 关键字，不能用
+        .value("Linear", ActType::None) // `None` is Python keyword
         .value("Relu", ActType::Relu)
         .value("Sigmoid", ActType::Sigmoid)
         .value("Tanh", ActType::Tanh)
diff --git a/src/operators/reduce_mean.cc b/src/operators/reduce_mean.cc
index 3a562abb..95e09dc5 100644
--- a/src/operators/reduce_mean.cc
+++ b/src/operators/reduce_mean.cc
@@ -6,8 +6,6 @@ ReduceMeanObj::ReduceMeanObj(GraphObj *graph, Tensor input, Tensor output,
     : OperatorObj(OpType::ReduceMean, {input}, {output}), keepDims(keepDims) {
     const auto size = input->getDims().size();
     if (_axes) {
-        // TODO 不需要这个，但需要处理负数，一对相反数应该不能同时出现。
-        // IT_ASSERT((*_axes).size() <= input->getDims().size());
         for (auto idx : *_axes) {
             if (idx < 0)
                 IT_TODO_HALT();